U.S. Pat. No. 3,692,178, assigned to the assignee of the present invention, shows a filter apparatus of the industrial, pressure liquid filtering type in which a compressed air powered vibrator depends by means of an input line and output line within a filter housing. The input line supplies an output line exhaust air with respect to said vibrator for causing same to vibrate, such lines extending axially in the housing along and adjacent to the filter element therein. Vibration of the vibrator and the air supply and exhaust lines thereof serves primarily to agitate the process liquid within such housing to be filtered, to reduce the tendency of solids in such process liquid to coat the filter element and thereby lead to premature clogging thereof.
Later U.S. Pat. No. 3,870,640, also assigned to the assignee of the present invention, shows a later development in which the vibrator is fixed to the bottom end of the filter element. The filter element depends from its top end which is fixedly supported within the filter housing. In this instance, the vibrator actually vibrates the filter element to which it is attached and thereby is intended to further reduce the tendency of solids in the process liquid surrounding the filter element to cake on and block the filter element.
However, testing of the latter apparatus has shown that the vibrator tends to laterally vibrate the bottom end of the filter element to a substantially greater amplitude than the top end of the filter element.
This is not a significant problem where the length of the filter element is relatively great. However, it becomes more of a problem where the length of the filter element is reduced. For example, the greater amplitude of vibration at the bottom end of the filter element may cause fatigue, stress and eventual structural damage at the top or bottom of such a filter element of reduced length. As a further example, coating by sticky process liquid impurities may tend to extend from the fixed top down over a greater portion of the length of the fiber element when the filter element length is reduced.
Accordingly, the objects and purposes of this invention include providing an improved vibrating filter apparatus in which vibration is applied to the end of the filter element which is attached to the housing, in which the lateral amplitude of vibration is substantially uniform from the top to the bottom of the filter element, in which there is a reduction of fatigue stress and coating at the top of filter elements and particularly reduced length filter elements and which is particularly adapted (but not limited) to use with filter elements of relatively short axial length, intended to be used in relatively compact spaces, and which are usable for example as a vibrating paint filter.
Accordingly, the objects and purposes of this invention include provision of a vibrating filter apparatus comprising a housing, filter element means in a housing, support means for supporting said filter element means in the housing, the support means including an elongate means in the housing connecting the filter element means in spaced relation to a wall of the housing, and vibrator means fixed to the support means between the housing wall and filter element means and actuable for vibrating the support means and thereby the filter element means.
Further objects and purposes of the invention will be apparent to persons acquainted with apparatus of this general type upon reading the present specification and inspecting the accompanying drawings.